In an article about Drupal's security process my colleague Jam made the claim that Drupal was the "the world's largest open source CMS." I was dubious at first, but his claim has some merit. The first paragraph of his article links to a study by Henrik Ingo of openlife.cc.
The study compared the projects on metrics like:
- developers active /day
- developers active / month
- developers active all time
- companies all time
Using those metrics Henrik declared Drupal to be one the largest "CMS" project and one of the largest open source projects (approximately 6th overall). However, there are some weaknesses in the study. The study has incomplete data about Drupal (missing devs/day, locs/day, companies all time) and probably incomplete/innacurate data on the other projects. The study was limited to a subset of total projects and only 2 CMS. In comparing the CMS, it considers Wordpress core only but seems to be looking at all Drupal contributed modules when calculating commits/day (or it sampled a very active day for Drupal core!).
If Henrik is interested I would be very willing to get him the data he needs from Drupal to do a more accurate comparison of CMS projects. To be clear: I think Henrik's analysis is very interesting and useful but could be improved to be more accurate.
Bold claim heads towards a lie: Standing Cloud's Drupal Press Release